Pyridotriazole brighteners



United States Patent ce 3,277,102

Patented Oct. 4, 1966 in Which M is a naphthalene ring which may carryhalo- PYRIDOTRIAZOLE BRIGHTENERS gen, alkyl, alkoxy and sulfo groups,and quaternary salts Bennett George Buell, Somerville, and Robert Sidneythemof' Long, Bound Brook, N.J., assignors to American Cyan- (3) Y amidCompany, Stamford, Conn., a corporation of 5 Maine No Drawing.Application Apr. 19, 1962, Ser. No. Z

188,897, now Patent No. 3,222,371, dated Dec. 7, 1965, HQN \\N/\\ whichis a division of application Ser. No. 87,754, Feb. N X W 8, 1961, whichin turn is a division of application Ser. No. 698,930, Nov. 26, 1957,now Patent No. 3,058,989,

dated Oct. 16, 1962. Divided and this applicationAug.

in which X may be hydrogen, sulfo or cyano; W may be hydrogen or sulfoand Z may be hydrogen, sulfo, amino 25 1964 Ser No 392 025 orsubstituted amino, and quaternary salts thereof.

1 Claim. (Cl. 260294.8) (4) Y N N U This application is a division ofapplication SN. 188,897, filed April 19, 1962, now Patent No. 3,222,371HN which application is in turn a division of SN. 87,754, 2

filed February 8, 1961, now abandoned said latter application being, inturn, a division of application S.N. 698,930, in Whlch Q y 0, NH of U ybe hydrogen filed November 26, 1957, now Patent No. 3,058,989. methyland T y be hydrogen or sulfa, and quaternary This invention relates toorganic fibers dyed with com- Salts thereofpounds of the structure:

\ \N N Q p J in which Q may be 0, NH or S; and V may be hydrogen,

N H alkyl, or aryl, and quaternary salts thereof.

in which Y may be hydrogen, alkyl, halogen, carboxy, im/N Y N carbalkoxyor carboxamido, I: may be one or two and R is an organic radical havinga 6-membered aromatic ring N-OON directly bonded to the triazole rings,the said group R HzN \N/\ y NH;

being the residue of a diazotizable amine. This invention furtherrelates to various new compounds of different in which the biphenylmoiety may carry one sulfonic acid structures which may be used to dyeand to brighten orgroup ortho to the biphenyl bond, and quaternary saltsganic fibers. More specifically, it relates to each of the thereof.

i NH;

separate and distinct groups of compounds listed below: in which D and Emay be hydrogen or sulfo, and quaternary salts thereof. (1) Y N (8) Y NN Y O HqN N I N N R, HzN N/ \N NH1 in which R may be hydrogen, halogen,alkyl, alkoxy, amino, acylamino, carboxy or phenyl, R may be hydrogen,alkyl or halogen, one of R and R not being hydrogen, and Y being definedas above in this and each sucin which F may be hydrogen or lower alkyl,and quaternary salts thereof.

ceed-ing formula and quaternary salts thereof. 9) Y N N Y 2) Y N\ m ff NM H2N \N \I/ T NH: HZN A i so N and quaternary salts thereof.

- 3 and quaternary salts thereof.

(11) Y N N K \N V v N/ mi in which L may be hydrogen, methyl, methoxyl,or chloro, and quaternary salts thereof.

in which B is a S-pyrimidyl radical, and quaternary salts thereof.

Q I I 6. in which G and G can be the residue of an aliphatic amine suchas ethanolamine or diet-hanolamine or of an aromatic amine oramino-sulfonic acid, and quaternary salts thereof.

Optical bleaching agents or brighteners are widely used in whitening andbrightening textile fibers of various types and are used both during themanufacture of textiles and during the operation of laundering fabrics.When optical bleaching agents or brighteners are applied to cloth, theblue fluorescence of the brightener, excited by ultraviolet irradiation,acts to neutralize the yellowish color of the cloth, producing aWhitening and brightening effect. Like any dye-stuff, a necessaryproperty is substantivity on the cloth. Brighteners are applied fromvery dilute solution, and unless they are substantive on the cloth, andthus are not readily washed :ofi, the eifect will not be achieved.Various types of compounds are used as brighteners and no brightner isequally substantive on all fibers. Most brighteners are relativelynon-substantive to one or another fiber, and consequently, differenttypes of brighteners must be used for different types of fabrics.Compounds which are suitable for cellulose fibers such as cotton, areoften not usable for synthetic fibers such as polyacrylonitriles orsuperpolyamides. Brighteners which show substantivity on most commontextiles are a great need in theindustry. While it is possible that nosingle brightener will everbe completely universal in its application,extensive research has been done in the search for at least a class ofcompounds which will be readily usable on any fiber or which willinclude members approaching universality of application.

The fluorescence of brighteners usually ceases immediately upon theremoval of the source of ultraviolet light. Phosphorescence, or thecontinuation of emission of visible light for an appreciable time afterremoval of the ultraviolet source, is not a necessary characteristic fora brightener. However, phosphoresoense is a property which is usuable inother ways and whose importance is rapidly increasing. A particularlyimportant application for phosphorescent compounds is in a machine inwhich the phosphorescent property is used for the purpose of weftstraightening. This is a process in the textile for maintaining fillthreads perpendicular to warped threads and selvages. The phosphorescenteifect allows control through the use of photocells which are activatedby the difierence in the period of light emission by fluorescentcompounds which phosphoresce, and those which do not. It is necessary touse phosphorescent compounds in such weft straightening because of thealmost universal use of brighteners in the finishing of cloth.Heretofore the control was through the fluorescence of a thread dyedspecially with a brightener, but now, with all threads being dyed Withbrighteners, the machine will not operate satisfactorily. Consequently,as described by Allen in his specification, Ser. No. 644,886, filedMarch 8, 1957, the control is now carried out by dyeing the controlthreads with a phosphorescent brightener, which thus continues emittinglight after the source of ultraviolet is removed.

For use in such an application, a compound must possess other propertiesbesides fiourescence and phosphorescence. It is necessary that thecompound be stable to various chemical and physical treatments whenapplied to the fiber or a fabric Without losing the phosphorescentproperty and without being removed from the fiber or the fabric. Mostcompounds, even when they show some phosphorescence, do not withstandthe harsh treatment.

necessary in the finishing of fabrics. Such treatment includes causticsolution at elevated temperatures, bleaching with hydrogen peroxide,steaming, and the like. There is thus a further. need in the dyestufffield for a class of compounds which will phosphoresce and also whichwill be stable under the harsh treatments of textile manufacture.

We have found that organic fibers can be dyed readily with compounds ofthe formula:

in which Y may be hydrogen, alkyl, halogen, carboxy,

carbalkoxy or carboxamido; n may be 1 or 2, and R is an organic radicalhaving a 6-membered aromatic ring directly bonded to the triazole rings,the said group R facture. We have further found that these dyestuffs canbe applied to a great variety of fibers, many of them being applicableto a greater or lesser extent to nearly all organic fibers and that,with variations in the structure, it is possible to increase thesubstantivity .of such compounds on specific classes of organic fibers.We have further found several distinct classes of new compounds aslisted above, which form a separate aspect of our invention. Theseclasses of compounds are not equivalent, their substantivity on variousfibers, their color (i.e., either fluorescence or self color as dyes),their phosphorescence and their stability to various treatments varyingfrom group to group.

It is an advantage of our invention that by proper selection ofsubstituents, it is possible to obtain dyeings on a wide range oforganic fibers. It is known that brighteners tend to be substantive oncellulosic fibers when they are linear coplanar molecules havingextended conjugation. It is surprising however, that the compounds usedin our invention go on cellulosic fibers even when these structuralcharacteristics are not prominent. Thus,2-phenyl-6-amino-2,3-pyridotriazole is substantive on cotton, althoughit is not an extended linear coplanar molecule, nor is it sulfonated.However, when the substituent on the triazole ring is a simple arylgroup, one obtains optimum brightening only on polyacrylonitrile fibers.Cotton brightening is obtained more readily With the use of morecomplicated substituents on the triazole ring or, better yet, evenbis-triazoles. It is a further advantage of our invention that onereadily obtains good acid solubility with pyridotriazoles, as contrastedto benzoor naphthotriazoles. It is a further advantage of our inventionthat the pyridotriazoles have good affinity to many kinds of syntheticfibers, especially polyamides and polyacrylonitriles. It is a stillfurther advantage of our invention that the pyridine ring in thepyridotriazole nucleus can be quaternized with the result that increasedsolubility is obtained and afiinity is obtained on polyacrylonitrilefibers at wide range of pHs.

In the preparation of compounds substantive to particular fibers,attention must be given to such factors as the type of fiber to betreated, the method of application (and .the solubility properties),whether the desired effect is phosphorescence of fluorescence (and iffluorescence, whether reddish-blue or greenish-blue) and similarfactors. When solubility in water is important, sulfonated aryl residuescan be used. However, sulfonation has the effect of decreasing afiinityon polyacrylonitrile fibers and similar non-cellulosic fibers. Greenershades of fluorescence can be attained by using suitable auxochromicsubstituents such as alkoxyl, dialkylamino or acylamino. One of the mostuseful and at the same time most unexpected advantages of the presentinvention is the wide variety of effects which can thus be built intothe products by proper selection of the starting materials.

The dyestuffs used in the present invention are conveniently prepared bycoupling an aromatic diazonium compound with a 2,6-diaminopyridine toform a 3-arylazo 2,6-diaminopyridine, which is then triazolized by anoxidative ring closure method using a mild oxidizing agent. If it isdesired to quaternize, this is achieved by reaction of the triazoleproduct with an alkylating agent such as an alkyl halide. Variousaromatic amines may be used to form the diazo component in the firststep of this preparation and proper selection of the amine makes itpossible to produce an optical bleaching agent with properties making itsuitable for use on various textile fibers. Examples of diazo-tizableamines which may be used in the reaction to produce compounds of theinvention are:

Aniline pand m-aminobenzoic acid Alkyl and aryl pand m-aminobenzoatespand m-aminobenzenesulfonic acid and their alkyl and aryl esters p- Andm-aminobenzenealkyl sulfones p- And m-aminoacetanilide p- Andm-aminobenzanilide p- And m-aminoanisanilide p- And m-aminobutyranilidep- And m-toluidine p- And m-chloroaniline p- And m-bromoaniline p- Andm-fluoroaniline o-Xylidine(3,4-dimethylaniline) p- And m-anisidine p-And m-nitroaniline 4-Aminobiphenyl Benzidine 4-aminostilbene4,4-diaminostilbene-2,2-disulfonic acid Z-naphthylamineZ-aminonap'hthalene-6-sulfonic acid 2-aminonaphthalene-S-sulfonic acidZ-aminonaphthalene-S,7-disulfonic acid 2-aminonaphthalene-6,8-disulfonicacid Z-(p-aminophenyl) -benzimidazole, benzoxazole and benzothiazole 5-And 6-aminobenzoxazole, -benzothiazole,

-benzimidazole, -benzotriazole 4-aminopyridine 3-aminopyridine6-methoxy-2-naphthylamine 6-chloro-2-nap'hthylamine These diazos arecoupled with various 2,6-diaminopyridines such as the following:

2,6-diaminopyridine 2,6-diamino-3-methylpyridine2,6-diamino-4-methylpyridine 2,6-diaminopyridine-4-carboxylic acid andits esters 2,6-diamino-3-bromopyridine 2,6-diamino-4-bromopyridine2,6-diaminopyridine-4-carboxamide The 3-arylazo-2,6-diaminopyridineintermediate is then oxidized with a mild oxidizing agent such as air inthe presence of copper sulfate, which results in ring closure to thetriazole derivative.

Pyridotriazoles in which the substituent on the triazole ring is apara-aminophenyl radical form an especially useful class of compoundsfor use in our invention, since they can be intermediates for thefurther preparation of more complicated brighteners and phosphorescentagents which can also be used in our invention. For example, the aminogroup on this phenyl ring can be diazotized and coupled into othercoupling components and, when the coupling component is so constitutedthat an o-aminoazo compound is formed, this too can be triazolized togive a bisor poly-triazole derivative. Thus, a bis-triazolo compound,either symmetrical or unsymmetrical is readily produced. The symmetricalbis-triazolo compounds are also readily produced from tetrazotization ofan aromatic diamine.

The fibers which may be used in preparing the dyed fibers of ourinvention include the various organic fibers used in the textileindustry, both synthetic and natural, since substantivity and otherproperties can be varied by the choice of the proper substituents andthe proper ring groupings in the brightener molecule to favorsubstantivity on any particular type of fiber. Among the fibers whichmay be used are the natural fibers, both cellulosic and non-cellulosic,such as cotton, wool, silk, and the like, and the synthetic fibers ofboth the cellulosic and noncellulosic types such as viscose rayon (i.e.,regenerated cellulose) cellulose esters such as cellulose acetate,polyacrylonitrile (either the homopolymer or copolymers with variouscomonomers such as vinyl pyridine, methyl acry: late, vinyl chloride,and the like), superpolyamides such as hexamethylene polyadipamide andpoly-omega-aminocaproamide, and superpolyesters such as polymericglycol- .terephthalate.

The brighteners to be used in our invention are especially useful onthose fibers for which most known brighteners have been notsatisfactory, such as the polyacrylics and the superpolyesters.

The brighteners may be applied as optical bleaching agents or asphophorescent agents from detergent compositions as ordinarilyformulated in the art, or from rinsing liquors for treatment duringtextile manufacture or after laundering operations.

In addition to being useful as brightening agents, the products used inthe preparation of our invention are also phosphorescent and thus thedyed fibers of our invention can be used where phosphorescence isimportant for special effects. 2-phenyl-6-amino-pyridotriazole isespecially useful for this purpose because of its phosphorescence andits substantivity to a wide variety of fibers. A particularly importantapplication for such phosphorescent dyed fibers is in a machine in whichthe phosphorescent property is utilized for the purpose of WeftStraightening, a process in the textile field for maintaining fillthreads perpendicular to warp threads and selvages. As described above,it is necessary for such application to have compounds which will standrather drastic treatment. It is an advantage ofthe dyed fibers of ourinvention that they are able to withstand the treatment with causticsolution at elevated temperatures and similar drastic treatments, andthat they show sufiicient phosphorescence.

Our invention includes not only organic fibers dyed with a broad classof pyridotriazole compounds, but also specific group falling within thisbroad class of compounds which have distinct and separate properties.These are all prepared in the same manner as described in general forthe class, i.e., by the coupling of an aromatic diazo compound into a2,6-diaminopyridine. Thus, in each class the pyridines which may be usedas the starting material are the same, but the diazotiazable amine whichis used varies with the class of compounds being considered. 4

In the class of compounds of the structure:

the amino compounds which may be used as starting materials include.p-Chloraniline p-Toluidine p-Anisidine p-Phenetidine p-Nitroanilinep-Phenylenediamine Monoacylated p-phenylenediamines;

such as p-acetamidoaniline p-Benzamidoaniline p-Propionylamimoaniline,and the like p-Aminobenzoic acid 4-aminodiphenyl 4-chlor-3-methylaniline4-bromo-3-ethylaniline 4-chlor-3-butylaniline 3,4-dichloroanilineS-chlor-p-anisidine m-Bromaniline, and the like.

The amines which may be used to prepare compounds of the class of thestructure:

include beta-naphthylamine, 2-aminonaphthalene-6-sulfonic acid,2-aminonaphthalene-S-sulfonic acid, Z-aminonaphthalene-4,6-disulfonicacid, 2-aminonaphthalene-5,7- disulfonic acid,2-aminonaphthalene-6,8-disulfonic acid, 2aminonaphthalene-4,S-disulfonic acid, 6 -metl1oxy-2- naphthylarnine,6-chloro-2-naphthylamine, and the like..

The amines which can be used to prepare the compounds of the structure:

QG XOHZWQZ include 4-aminosti1bene, 4-aminostilbene-2,2'-disulfonic 8acid, 4-aminostilbene-2-sulfonic acid, 2-cyano-4-aminostilbene,4-amino-4'-nitrostilbene-2,2'-disulfonic acid, 2-(4-aminostilbyl)-methyl sulfone, and the like.

The amines which may be used to prepare the class of compounds of theformula:

include dehydrothiotoluidine, dehydrothiotoluidine sulfonic acid,4'-amino-2-phenyl benzoxazole, 4'-amino-2-.

pheny-l-benzimidazole, and the like.

In the preparation of compounds of the class:

M. EN 3;

the following amines may be used; 5- or 6-aminobcnzothiazole,2-methyl-5- or 6-aminobenzothiazole, 2-pheny-l- 5- or6-aminobenzothiazole, 5- or 6-aminobenzoxazole, 2-,

phenyl-S- or fi-aminobenzoxazole, 2-methyl-5- or 6-amino- 'benzoxazoles,S-aminobenzimidazole, 2-methyl-5(6)-aminobenzimidazole,2-phenyl-5(6)-aminobenzimidazo1e, and the like.

In the preparation of compounds of the structure:

can be prepared by starting with such diamines as4,4'-diaminostilbene-2,2'-disulfonic acid and 4,4'-diaminostilbene, aswell as 4-amino-4'-nitro diamino stilbene and the correspondingdisulfonic acid, in which case the preparation requires several steps, adiazotization of the amino group followed by coupling, after which thenitro group is reduced and the diazotization and coupling is repeated.These products are yellow fluorescent dyes.

Compounds of the structure:

-QrQ N N F can be prepared starting with such compounds as4,4'-diaminodiphenylamine, 4,4-diaminodip:henyl methyl amine,4,4'-diaminodiphenyl ethyl amine, 4,4'diaminodiphenyl butyl amine, andthe like.

The starting material for compounds of the structure:

9 is 3,7-diamino-dibenzothiophene-S,5-dioxide.

Compounds of the formula:

are prepared from 4,4'-diamino-N,N-diphenylurea.

Compounds of the structure:

N N W Q in which L may be hydrogen, methyl, methoxyl, or chloro, aresimilarly prepared by a second dia-zot-ization and coupling andtriazolization, this time by coupling into 6-amine-5-substituted2-para-sulfophenyl benzotriazole and performing a second triazolization.The substituent on the coupling component for the second triazolizationcan be hydrogen, methyl, methoxyl or chloro.

Compounds of the type:

in which B is a S-pyrimidyl nucleus are obtained by coupling adiazotized amino pyrimidine into a 2,6-diamino pyridine andtriazolizing. For this purpose one can use 5- amino pyrimidine,substituted S-amino pyrimidines, and the like.

Compounds of the type:

are prepared by reacting the intermediate 2-p-amin0-phenyl-6-aminopyridotriazole with cyanuric chloride, fol- N/ \N/ NH:

lowed by further reaction of the product with aliphatic amines such asalkyl amines or preferably substituted alkylamines (ethanolamine,diethanolamine, morpholine, etc.) or with aromatic amines oraminosulfonic acids such as aniline, sulfauilic acid, and the like.

In all these various classes of dyestuffs, as well as in the principalinvention of the dried fibers, the pyridine ring in the pyridotriazolemoiety can be quatern-ized by treatment with an alkyiating agent to forma quaternary compound on the pyridine ring nitrogen. Examples ofalkylating agents which may be used are methyl iodide, ethyl bromide,butyl bromide, benzyl bromide, dimethyl sulfate, d-iethyl sulfate,ethylene chlorohydrin, betadiethylamino ethyl chloride, alkyl tosylatessuch as methyl tosylate, and the like. Among the purposes of suchquaternization are to get increased Water solubility of the brightenermolecule and to permit the application of the dyestuff over a broaderrange of pH. The quaternized brighteners are in general equivalent tothe unquaternized brighteners, and in some cases superior, insubstantivity to various fibers. Consequently, the quaternizledcompounds and the fibers dyed with them form a part of our invention.

Our invention can be illustrated by the following examples in whichparts are by weight unless otherwise indicated.

Example 1 A mixture of 27.9 parts of 2,6-diamino-3phenylazopy-ridine(commercially available as Pyridium or Azoimide), 450 parts of ethanol,70 parts of water and 180 parts of concentrated ammonium hydroxide isheated under reflux with stirring. A hot solution of 170 parts of coppersulfate in 500 parts of Water and 300 parts of concentrated ammoniumhydroxide is added. After heating for several hours, an additionalportion of 25 parts of copper sulfate in parts of water and 45 parts ofconcentrated ammonium hydroxide is added and heating is continued untilthe reaction is substantially complete, as shown by disappearance of thestarting material. After cooling the mixture, the product is removed byfiltration and Washed thoroughly with dilute ammonium hydroxide andwater to remove the copper. The product is purified by dissolving in 400parts of water, 450 par-ts of ethyl alcohol, and parts of concentratedhydrochloric acid. After treatment with a decolorizing agent andfiltering, the filtrate is treated with 55 parts of concentratedhydrochloric acid. On cooling, the hydrochloride of the productseparates as cream colored rods, is removed by filtration and thenwashed with alcohol.

Example 2 HzN \N/ N/ S O Na A diazonium solution is prepared from 2.75parts of 4-amino-stilbene-2-sulfonic acid by diazotization with sodiumnitrite. The diazonium solution is combined with a solution of 1.09parts of 2,6-diaminpyridine in 75 parts of acetic acid, 50 parts ofwater and 2.2 parts of concentrated hydrochloric acid. With stirring, 50parts of a saturated solution of sodium acetate is added slowly andstirring is continued until coupling is complete. The solid aminoazocompound is removed by filtration and washed with water and is thentaken up in 90 parts of 95% ethanol, 22 parts of concentrated ammoniumhydroxide and 20 parts of water. The mixture is heated to the boilingpoint and a hot solution of 17 parts of copper sulfate, 75 parts ofwater, and 36 parts of concentrated ammonium hydroxide is added and themixture is heated at the reflux temperature with stirring until thereaction is complete. After the mixture is cooled, the solid is removedby filtration, slurried in dilute hydrochloric acid and then againisolated by filtration. I For purification, .it is dissolved in methylCellosolve containing a small amount of sodium hydroxide and afterclarification with a decolorizing agent, the product is isolated fromthe filtrate by adding additional sodium hydroxide solution andsaturated sodium acetate. After stirring, the product is isolated as alight tan sodium salt.

Example 3 The procedure of Example 2 is followed, except that anequivalent quantity of sulfanilic acid is substituted for the4-aminostilbene-2-sulfonic acid. The product is obtained as an almostwhite sodium salt.

Example 4 A diazonium solution is prepared by diazotizing 3.38 parts of4-a'minobiphenyl with sodium nitrite in acetic acid at 30 C. Thediazonium solution is combined with a solution of 2.18 parts of2,6-diaminopyridine in 100 parts of acetic acid, 100 parts of Water, and4 parts'of concentrated hydrochloric acid. With stirring, 75 parts ofsaturated sodium acetate solution is added. The mixture is stirred untilthe coupling is complete and the light orange coupling product isremoved by filtration and trie azolized by oxidation with copper sulfateand ammonium hydroxide as described in Example 2. The product ispurified by dissolved in about 600 parts of hot methyl Cellosolve andexcess concentrate hydrochloric acid, clarifying with a decolorizingagent and isolating by the addition of 300 parts of water and excessammonium hydroxide to the filtrate.

Example The procedure of Example 4 is followed except that an equivalentquantity of 2,6-diamino-3-bromo-pyridine is used in place of the2,6-diaminopyridine and an equivalent quantity of aniline is used inplace of the 4-aminobiphenyl. The corresponding methyl compound is prepared by starting with 2,6-diamino-3-methyl-pyridine.

Example 6 The procedure of Example 4 is followed except that anequivalent quantity of 2,6-diamino-4-picoline is used in place of the2,6-diaminopyridine.

Example 7 A diazonium solution is prepared by diazotizing 13.8 parts of4-nitro-aniline with sodium nitrite. The solution is combined with asolution of 10.9 parts of 2,6-diaminopyridine in 500 parts ofacetic'acid, 500 parts of Water and 18 parts of concentratedhydrochloric acid. With stirring, the mixture is neutralized withsaturated sodium acetate solution and the bright redo-aminoazo productwhich forms is removed by filtration and washed with water. Thiso-aminoazo product is taken up in 540 parts of ethanol, 150 parts ofwater, and parts of concentrated ammonium hydroxide. The mixture isheated and a hot solution of 125 parts of copper sulfate, 500 parts ofwater, and 225 parts of ammonium hydroxide is added. The mixture isheated at the reflux temperature until the triazolization is complete,cooled, and the produced is removed by filtration. This nitro compoundis then re-.

' duced to the corresponding amino compound by the following procedure:

The nitro compound is added to parts of Water, 45 parts of ethanol and120 parts of 5 N sodium hydroxide. To the mixture at 70-85 C. is added70 parts of sodium hydrosulfite. net is isolated by filtration andwashed alkali-free with water. The amino compound is purified by theclarificat-ion with a decolorizing agent from solution in 250 parts ofhot 4 N hydrochloric acid, and isolated by making the filtrate alkalineby the addition of ammonium hydroxide.

Example 8 To 0.75 part of 6-amino-2-(p-aminophenyl)-2-pyrido[2,3-d]-v-triazole (prepared as in Example 7) is added 25 parts ofpyridine and 0.7 part of p-anisoyl chloride;

The mixture is heated at the I reflux temperature for a short time andis then drowned in ice. The solid product which forms is removed byfiltration and washed with water and is purified by recrystallizationfrom methyl Cellosolve, giving the product in the form of prisms with.

a melting point of 293296 C.

By the use of equivalent amounts of other acyl halides in place of thep-anisoyl chloride such as acetyl chloride, butyryl chloride, stearylchloride, benzoyl chloride, 2,4-

After stirring and cooling, the prod-.

dichlorobenzoyl chloride, and similar compounds, the correspondingacylarnide compounds are obtained.

Example 9 A diazonium solution prepared by diazotizing 2.26 parts of6-amino-2-(p-aminophenyl)-2-pyrido 2,3-d-v-triazole (prepared as inExample 7) is combined with a slurry of 2.54 parts of sodiumnaphthionate in 100 parts of water, 4 parts of hydrochloric acid and 50parts of acetic acid. With stirring, 50 parts of saturated sodiumacetate solution is added and the stirring is continued until thecoupling is complete (4 hours). The o-aminoazo product is removed byfiltration and triazolized by oxidation using the procedure described inExample 7. Purification of this bis-triazolyl product is eifected bydissolving the product in 400 parts of hot monoethanolamine, and 4 partsof N sodium hydroxide solution. After clarification with a decolorizingagent, 100 parts of water is added to the filtrate and the sodium saltof the product is salted out by the addition of sodium hydroxide, givinga crystalline yellow product.

Example 10 A tetrazonium solution prepared by tetrazotizing 1.86 partsof benzidine in 100 parts of water, 9 parts of hydrochloric acid and 8parts of 1 N sodium nitrite solution is combined with a solution of 2.4parts of 2,6-diaminopyridine in 100 parts of water and 5 parts ofconcentrated hydrochloric acid. The mixture is neutralized to Congo Redindicator by addition of saturated sodium acetate solution (about 60parts). The color changes from blpe-black to dull orange. After stirringthe mixture, the solid azo product is removed by filtration.

For conversion to the triazole derivative the disazo product from aboveis slurried in a hot mixture of 150 parts of pyridine and 20 parts ofconcentrated ammonia. A half-portion of a solution of 24 parts of coppersulfate, 100 parts of Water and 40 parts of ammonia is added and themixture is heated for several hours. The other half of the coppersulfate solution is then added and the mixture is heated until thereaction is complete. The solid material is removed by filtration andpurified by recrystallization from about 300 parts ofN-methyl-2-pyrrolidone.

Example 11 A tetrazonium solution is prepared by tetrazotizing 37 partsof 4,4'-diaminostilbene-2,2'-disulfonic acid. This is done by firstdissolving the stilbene derivative in 150 parts of water and 7 parts of5 N sodium hydroxide solution. Twenty-one parts of 1 N sodium nitritesolution is added and after filtering, the solution is poured into amixture of 200 parts of ice and 16 parts of hydrochloric acid. Afterstirring for a short period, the excess nitrite is destroyed withsulfamic acid.

To the above brown slurry is added a solution of 2.4 parts of2,6-diamino-pyridine in 150 parts of Water and 5 parts of concentratedhydrochloric acid. Saturated sodium acetate solution is added until themixture is neutral to Congo Red indicator. Coupling takes place rapidlyand after stirring, the solid disazo compound is removed by filtrationand triazolized by the procedure described below.

The solid product is dissolved in a hot mixture of 150 parts of pyridineand 20 parts of ammonium hydroxide. To this is added a half portion of asolution of 24 g. copper sulfate, 100 parts of water and 20 parts ofconcentrated ammonia. After heating a short period, the second halfportion of the copper sulfate solution is added and the mixture isheated until the reaction is complete. The solid bis-triazole compoundis removed by filtration.

The product may be purified by recrystallizing from hot dimethylformamide containing a small amount of caustic and then precipitatingthe product from the cooled dimethylformamide filtrate by addition ofwater and hydrochloric acid to the neutral point.

SOa a A diazonium solution prepared by diazotization of 2.26 parts of6-amino-2-(p-aminophenyl)-2-pyrido-[2,3-d]- triazole with sodium nitritein hydrochloric acid solution is combined With a solution of 3.04 partsof 6-amino-2H- S-methyl-Z-(p-sulfophenyl)-benzotriazole in 160 parts ofacetone, 100 parts of water and 4 parts of concentrated hydrochloricacid. With stirring, 50 parts of saturated sodium acetate solution isadded and the mixture is then stirred until the coupling is complete (4hours). The resulting o-aminoazo product is removed by filtration andthen triazolized by oxidation with copper sulfate using the proceduredescribed in Example 6. The product is isolated as the sodium salt andpurified by treatment with decolorizing charcoal in hot dimethylformamide solution, giving the product as the purified sodium salt.

Example 13 The procedure of Example 1 is followed except that anequivalent amount of 2,6-diaminopyridine-4-carboxylic acid is used inplace of the 2,6-diaminopyridine.

Example 14 butylaniline, para-propylaniline or para-aminobenzoic acid.

Example 15 The procedure of Example 4 is followed using an equivalentquantity of 3,4-dimethylaniline in place of the 4-aminobiphenyl.Similarly, other substituted products are obtained if one uses3-chloro-4-methyl-aniline or 4-chloro-3-methylaniline in place of thedimethylaniline.

Example 16 The procedure of Example 4 is followed using an equivalentquantity of beta-naphthylarnine in place of the 4-aminobiphenyl.Corresponding substituted compounds are obtained by using suchderivatives as Bronners acid, Dahls acid, amino J acid and amino G acidin place of beta-naphthylamine.

Example 17 The procedure of Example 4 is followed using 4-aminostilbenein equivalent quantities in place of the 4-aminobiphenyl. The product isa good brightener for nylon.

Example 18 A mixture of 30 parts of 2-cyano-4-nitrotoluene, 22 parts ofbenzaldehyde and parts of piperidine is heated at 125 l40 C. until thereaction is substantially complete. The melt is dissolved in 160 partsof hot glacial acetic acid and on cooling the crystalline solid whichforms is filtered. To a boiling suspension of 9 parts of the aboveproduct in 250 parts of 95% alcohol is added a solution of 44 parts ofhydrated stannous chloride and 44 parts of concentrated hydrochloricacid. The mixture is heated at reflux temperature until reduction issubstantially complete. The mixture is then cooled and the solid isremoved by filtration. It is purified by surrying in dilute sodiumhydroxide solution.

A solution of 4.4 parts of the 4-amino-2-cyanostilbene so produced in120 parts of acetic acid is prepared and to it is added 8.4 parts ofconcentrated hydrochloric acid. Twenty-two parts of N/ 1 sodium nitritesolution is then added with cooling, and after stirring for a shortperiod the excess nitrite is discharged by the addition of sulfamicacid. The diazo solution is then used to couple with a solution of 3parts of 2,6-diamino-pyridine in parts of acetic acid, 100 parts ofwater and 4 parts of concentrated hydrochloric acid by the procedure ofExample 4.

Example 19 To a hot well-stirred solution of 22.9 parts of the sodiumsalt of benzaldehyde ortho sulfonic acid and 16.2 parts ofS-nitro-orthot-oluonitrile in 40 parts of pyridine there is added 2parts of piperidine and 9.2 parts of sodium bicarbonate. The mixture isheated on a steam bath until the reaction is substantially complete.During the heating period, an additional 40 parts of pyridine is added.The mixture is then diluted with 200 parts of water and the pyridine isstripped out with steam. The mixture is cooled with ice and theprecipitated product is isolated by filtration and dried.

To a vigorously stirred mixture of 29.5 parts of iron powder, parts ofwater and 4 parts of glacial acetic acid heated under reflux there isgradually added 11.8 parts of the product of the preceding paragraph.The mixture is heated under reflux with good stirrinng until thereaction is substantially complete and then is neutralized with a smallexcess of soda ash. The iron sludge is filtered and washed with hotmethanol and the filtrate and washings are treated hot with charcoal.The mixture is filtered and the filtrate is acidified with concentratedhydrochloric acid. The precipitated 4-amino-2-cyanostilbene-2'-sulfonicacid is isolated by filtration and purified by recrystallization fromalcoholic methanol follower by reprecipitation with hydrochloric acid.

An equivalent quantity of the above product is used in the procedure ofExample 2 in place of the 4-aminostilbene-Z-sul-fonic acid used in thatexample.

The procedure of Example 2 is followed using an equivalent quantity of4-amino-4'-nitrostil-bene-2,2-disulfonic acid. The nitro group is thenreduced and acylated as in Example 8, using benzoyl chloride.

Example 21 Example 22 The procedure of Example 4 is followed using anequivalent quantity of 4'-amino-2-phenylbenzoxazole in place of.

the 4-aminodiphenyl.

A sulfonated derivative of the 17 7 Example 23 The procedure of Example4 is followed using an equivalent quantity of4-amino-2-phenylbenzimidazole in 10 place of the 4-aminobiphenyl.

18 Example 27 pf I 5 HgN \N/\N SOQH \N, NH:

The procedure of Example 11 is followed using an equivalent quantity ofbenzidine-Z-sulfonic acid in place of diaminosti-lbene disultonic acid.

- Example 28 Example 24 N N HzN \N on The procedure of Example 4 isfollowed using an equivalent quantity of 5-aminobenzothiazole in placeof 4-aminodiphenyl. Similarly, equivalent quantities of S-amino-Z-methylbenzothiazole and S-arnino-Z-phenylbenzothiazole can be used togive the corresponding substituted products.

Example 25 The procedure of Example 4 is followed using 6-amino- 2-phenylbenzoxazole in equivalent quantities in .place of4-alminodipheny-l. If 6 aminobenzox-azo1e or 6-arnino-2-methylbenzoxazole is used in equivalent quantities the correspondingbrightener compound is obtained.

Example 26 N o--orr HzN The procedure of Example 4 is followed using anequivalent quantity of 5 (6)-amino-2-methylbenzimidazole in place of4-aminodiphenyl.

N NH- v V N \N/ Q Q s The procedure of Example 10 is followed using anequivalent quantity of 4,4'diaminostil1bene in place of the benzidine.The corresponding monosullfonic acid is prepared if the procedure ofExample 11 is followed with 4,4'-diaminostilbene mono'sulfom'c acid.

Example 29 y NH:

The procedure of Example 10 is followed using an equivalent quantity of4,4'-diaminodip henylamine in place of the benzidine. The correspondingalkyl compounds are prepared if equivalent quantities of4,4-diphenylmethylamine and 4,4'-diphenylbutylamine are used in place ofthe 4,4-diphenylaknine above.

7 Example 30 The procedure of Example 10 is followed using an equivalentquantity of 4,4'-diaminodiphenylu-rea in place of the benzidine.

Example 32 v HzN V The procedure of Example 9 is used using2-naphthylamine-S-sul-fonic acid in place of naphthionic acid. Thecorresponding disulfonated product is obtained by using an equivalentquantity of 2-naphthylamine-4,6-disulfonic acid in place of thenaphthionic acid. If the naphthionic acid is replaced withbeta-naphthylamine the corresponding unsulfonated product is obtained.

Example 33 A mixture of 1 part of -amino-2-phenyl-(2)-pyrido[2,3-d]-v-triazole (prepared as in Example 1), 40 parts of methanol and44 pants of methyl iodide is heated as the reflux temperature until thereaction is completed, and is then evaporated to dryness. The yellowsolid which is obtained is purified by precipitating from a methanolsolution by the addition of diethyl ether, giving one part of whitesolid product which is soluble in water.

Similar quaternary derivatives are obtained by the use of ethyl bromide,butyl bromide, benzyl chloride, allyl bromide, and ethylene chlorohydrinin place of the methyl iodide, although the chlorides and bromides takea longer time to give complete reaction. In cases where the solubilityof the product was not sufliciently high, 2 improved characteristics maybe obtained by metathetical exchange of the anion to form thecorresponding acetate or nitrate or other salt.

Example 34 A mixture of 21 parts of 5-amino-2-phenyl-(2)-pyrido- [2,3-d]-v-triazole, 24 parts of diethylsulfate and 100 parts of ethanol isheated at the reflux temperature until the reaction is complete.

The crystalline solid which forms is removed by filtration.

By using an equivalent amount of dimethyl sulfate in place of thediethyl sufate, the corresponding methyl compound is obtained.

Example 35 HIN Example 36 The procedure of Example 33 is followed usingthe product. of Example 6 instead of the product of Example 1. Theproduct of the above structure shows more aflin- 75 20 ity for somefibers thandoes the product of Example 6 and on other fibers isequivalent to the unquaternized product.

Example 37 i HIN \N N Br until the coupling is completed. An orangeproduct is filtered and allowed to drain.

The product is takenup in 92 parts of ethanol, 16 parts of water, 45.8parts by volume of concentrated ammonia and parts of pyridine and themixture is heated with stirring. A hot solution of 38.9 parts of coppersulfate in 115 parts of water and 68.7 parts by volume of concentratedammonia is added, a stream of air is introduced, and the mixture isrefluxed with stirring until the reaction is substantially complete. Itis cooled and the product is filtered, washed with water and diluteammonia, dissolved in hot dilute ethanolic hydrochloric acid, filteredhot with charcoal and filtered again. The clarified solution is leftstanding and gradually yields orange crystals; A hot dilute ethanolicsolution of this product is clarified with charcoal made alkaline tophenolphthalein and treated with sodium hydrosulfite at theboil. A shinyyellow product is filtered and dried at 60 C.

Example 38 To 40 parts by volume of concentrated sulfuric acid is addedwith stirring, 2.8 parts (0.04 mole) of finely ground sodium nitrite,keeping the temperature below 50 C. The resulting solution is cooled to5 C. and a solution of 4.0 parts of 4-arnino-pyridine in 10 parts ofglacial acetic acid is added dropwise at temperatures below C. Themixture is stirred until diazotization is complete. The diazoniumsolution is combined with a solution of 0.04 mole of 2,6-diaminopyridinein parts of glacial acetic acid at temperatures below 15 C. The brownsolution is stirred until coupling is complete and then drowned on partsof ice, and neutralized to pH of 7.8 with dilute caustic. The product isthen filtered and dried and-recrystallized from absolute methanol.

The coupling product is added to a hot solution of 5.0 parts-of coupersulfate, 12.5 parts of water and 25 parts of pyridine and the mixture isrefluxed until the reaction is complete. It is then steam stripped toremove the pyridine, acidified, cooled and filtered. The orange productis dissolved in hot dilute acid, filtered and dilute caustic.

solution is added to precipitate the product. 'This is then dissolved inhot alcoholic HC1 and precipitated with con-. centrated ammonia toinsure removal of .the copper ions. A cream colored product is filtered,washed with water,

and driedat 100 C.

Example 39- tration. This solution is used in the following dyeing pro-.

cedure: I v

To a mixture of 98.5 parts of water and 1.5 parts'of 10% acetic acidsolution is added parts of 0.005 brightener solution from above. A -partpiece of polyacrylonitrile fabric (Orlon) is added and the temperatureis raised to the boiling point and held there for about 30 minutes. Thefabric is removed, rinsed in water and dried in the air. It is muchwhiter and brighter in appearance than a piece of the untreated Orlonfabric.

Example 40 On 0.005% solution of the brightener of Example 33 isprepared by dissolving 1 part of brightener in 1000 parts of boilingwater and diluting with water to the 0.005% concentration.

To a mixture of 98.5 parts of water and 1.5 parts of acetic acidsolution is added 50 parts of the 0.005 brightener solution. To theresulting acetic acid solution of the brightener is then added a 5-partpiece of Orlon fabric (polyacrylonitrile). The temperature is raised tothe boiling point and held there for 30 minutes. The fabric is removed,rinsed in water and dried. It is much whiter and brighter in appearancethan a piece of the untreated Orlon fabric.

Example 41 To a solution of 0.025 part of the product of Example 1 isadded 0.5 part of sodium sulfate. A piece of cotton cloth weighing 5.0parts is added and the dyebath is heated to 130 F. After minutes,another 0.5 part of sodium sulfate is added and heating is continued foranother 15 minutes. The cloth is then removed, rinsed at 80 F., anddried. The dyed cloth is exposed to UV light in a darkroom. Afterremoving the source of the UV light it is observed that the emission ofvisible light continues for a noticeable period.

The dyed cloth is immersed in a 5% sodium hydroxide solution and steamedat one to two pounds pressure for 1 /2 hours. The cloth is then rinsedand immersed in a bleaching solution formulated with hydrogen peroxideand sodium silicate, after which it is then steamed again at one to twopounds pressure for one hour. After rinsing in dilute acetic acid andwater and then drying, the dyed cloth is again exposed to UV light.After the removal of the source of the UV light, the emission of visiblelight I continues for a noticeable period, showing that thephosphorescent property of the cloth is retained after the abovefinishing treatments, typical of those to which fabrics are subjected inmanufacture.

Example 42 Compounds selected from the group consisting of (1) those ofthe formula:

N N HzN \N N/ \SO/ \N NH:

wherein Y is selected from the group consisting of hydrogen, alkyl,halogen, carboxy, carbalkoxy and carboxamide, and (2) quaternary saltsof (1).

References Cited by the Examiner UNITED STATES PATENTS 3,049,438! 8/1962 Buell et a1. 117-335 3,058,989 10/ 1962 Buell et a1 260-2963,222,371 12/1965 Buell et a1 260294.8

WALTER A. MODANCE, Primary Examiner.

A. L. ROTMAN, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,277,102 October 4, 1966 Bennett George Buell, et al.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 4, lines 6 and 7, for "This is a process in the textile formaintaining" read This is a process in the textile field for maintainingcolumn 8, lines 7 to 12, for the lower right-hand portion of the formulareading read same column 8, lines 59 to 64, for the lower left-handportion of the formula reading read column 10, line 18, for "dried" readdyed line 59, for "dissolved" read dissolving column 16, line 37, for'lower" read lowed column 16, lines 53 to 58, for that portion of theformula reading read column 18, lines 38 to 44, the formula shouldappear as shown below instead of as in the patent:

column 19, line 14, for "as" read at column 20, line 55, for "couper"read copper Signed and sealed this 5th day of September 1967.

(SEAL) Attest:

EDWARD J. BRENNER ERNEST W. SWIDER Attesting Officer Commissioner ofPatents

